Limnology of reservoirs in the Southeastern part of São Paulo State, Brazil. V. Typification by abiotics factors and chlorophyl a.

Abstract

This paper is part of a study made in 1979 which envolved abiotic and biotic factors of 17 reservoirs. The identification of types was made by cluster analysis and a simple technique of corochromatic comparisons. This technique showed itself good for to do the limitation among the reservoir types. The results showed six types that can be recognized by the median values and 25% - median í  75% values of some variables. Type 1 showed 6.4 mg/L ionic content; 5.0 µS/cm electrical conductivity; 0.07 meq/L alkalinity; zero calcium, 0.2 mg/L Si; 0.5 mg/L K; 0.2 mg/L Mg; and 11 µg/L chlorophyll a. Type'2: 16.3 mg/L ionic content; 20 - 23 - 24 µS/cm electrical conductivity; 0.13 - 0.14 - 0.15 meq/L alkalinity; 0 - 0 - 1.1 mg/L Ca; 0.4 - 0.5 - 0.9 mg/L Si; 1.0 - 1.2 - 1.3 mg/L K; 0.4 - 0.5 - 0.6 mg/L Mg; and 3 í  5 - 10 µg/L chlorophyll a. Type 3: 27.9 mg/L ionic content;. 35 í  39 - 45 µS/cm electrical conductivity; 0.21 - 0.28 - 0.32 meq/L alkalinity; 2.1 - 2.8 - 3.3 mg/L Ca; 1.1 - 1.8 - 2.5 mg/L Si; 1.8 - 2.0 - 2.2 mg/L K, 0.8 - 1.0 - 1.1 mg/L Mg; and 4 - 6 - 9 µg/L ch1orophyll a. Type 4: 158.0 mg/L ionic content; 225 µS/cm electrical conductivity; 0.71 meq/L alkalinity; 13.1 mg/L C; 1.5 mg/L Si; 4.75mg/L K; and 1.88 mg/L Mg. Type 5: 226.1 ionic content; 300 µS/cm conductivity; 1.69 meq/L alkalinity; 18.1 mg/L Ca; 2.6 mg/L Si; 8.61 mg/L K; 3.15 mg/L Mg; and 58 µg/L chlorophyll a. Type 6: 272.3 mg/L ionic content; 360 µS/cm electrical conductivity; 2.52 meq/L alkalinity; 21.1 mg/L Ca; 2.9 mg/L Si; 10.11 mg/L K; 3.54 mg/L Mg; and 60 µg/L chlorophyll a.